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**Mathhelpz** **Q-2e **One type of candy costs 60 cents a pound while a second type costs 80 cents a pound. How many pounds of each type must be combined in order to produce 20 pounds of a mixture worth *75 *cents a pound?

I got the answer though,

type 1 =x

type 2 =y

x+y=20

y=20-x

60x+80y=75(x+y)

60x+80y=75x+75y

simplify

5y=15x

sub in y=20-x

5(20-y)=15x

100-5x=15x

100=20x

x=5

plug 5 into y=20-x

y=15

Could someone help me form a matlab script?

You have the pair of equations:

$\displaystyle x+y=20$

$\displaystyle 60x+80y=75\times 20$

or in matrix form:

$\displaystyle \left[ \begin{array}{cc}1&1\\60&80\end{array}\right] \left[ \begin{array}{c}x\\y \end{array} \right] = $ $\displaystyle \left[ \begin{array}{c}20\\1500 \end{array} \right] $

So is we set:

$\displaystyle

\bold{x}= \left[ \begin{array}{c}x\\y \end{array} \right]

$

We can write:

Code:

A=[1,1;60,80];
Z=[20;1500]
X=A\Z

or of you prefer:

Code:

A=[1,1;60,80];
Z=[20;1500]
X=inv(A)*Z

CB